29-09-2021, 05:45 PM
(This post was last modified: 29-09-2021, 05:48 PM by ppppenguin.)
The resolution of digital systems is specified as visible pixels by visible lines plus i for interlace or p for progressive. The number of pixels per line is standardised at 1280 for 720 line systems, 1920 for 1080 lines and 3840 "4K" for 2160 lines.
1080/50i (or 1080i50) is 1920x1080, 50 interlaced fields per second
576/50i is old fashioned 625
720/30p is 1280x720 progressive, 30 progressive fields per second
720 line systems, always progressive scan, have a total of 750 lines, 30 of which are vertical blanking.
1080 line systems, inerlaced or progressive scan, have a total of 1125 lines, 45 of which are vertical blanking.
The horizontal blanking interval varies with standard to give the same 74.25MHz or 148.5MHz luminance sampling rate.
The Cb and Cr colour difference sampling rates are each half the luminance rate.
The digital sync pulses are sequences of digital codes that cannot occur in a real picture.
Charles Poynton's books "A technical Introduction to Digital Video" and "Digital Video and HDTV" are both very good. If you google the author I think a lot of his material is freely available online. His explanations are good. John Watkinson's classic "The Art of Digital VIdeo" is excellent but may be rather dated unles he's revised it recently.
This wiki page is basic but OK: https://en.wikipedia.org/wiki/Serial_digital_interface
1080/50i (or 1080i50) is 1920x1080, 50 interlaced fields per second
576/50i is old fashioned 625
720/30p is 1280x720 progressive, 30 progressive fields per second
720 line systems, always progressive scan, have a total of 750 lines, 30 of which are vertical blanking.
1080 line systems, inerlaced or progressive scan, have a total of 1125 lines, 45 of which are vertical blanking.
The horizontal blanking interval varies with standard to give the same 74.25MHz or 148.5MHz luminance sampling rate.
The Cb and Cr colour difference sampling rates are each half the luminance rate.
The digital sync pulses are sequences of digital codes that cannot occur in a real picture.
Charles Poynton's books "A technical Introduction to Digital Video" and "Digital Video and HDTV" are both very good. If you google the author I think a lot of his material is freely available online. His explanations are good. John Watkinson's classic "The Art of Digital VIdeo" is excellent but may be rather dated unles he's revised it recently.
This wiki page is basic but OK: https://en.wikipedia.org/wiki/Serial_digital_interface
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
